Power nozzle for a floor cleaning apparatus

ABSTRACT

A rolling brush used in a vacuum cleaner, comprising a frame, a rotating cylinder attached to the frame via a pivot and having the rolling brush on its circumference, an transmission shaft of a motor, a first drive belt runs around a movable pulley assembly and the transmission shaft of the motor so that the movable pulley assembly can drive the rotating cylinder to rotate. The movable pulley assembly can move between two positions and in the first position the rotating axis of the movable pulley assembly is remote from the rotating axis of the transmission shaft of the motor with the first belt tensioned, and in the second position the rotating axis of the movable pulley assembly is close to the rotating axis of the transmission shaft of the motor with the first drive belt being free from tensioned. The driving of the movable pulley assembly can be intermitted simply by moving the movable pulley assembly into the second position without shutting down the motor.

RELATED APPLICATION

The present application Claims foreign priority under Chinese Patent Application, No. 200510038317.5, filed Feb. 5, 2005 currently pending before the China Patent and Trademark Office.

FIELD OF INVENTION

The invention relates to a vacuum cleaner nozzle, and more particularly to a power nozzle for a floor cleaning apparatus.

DESCRIPTION OF THE RELATED ART

In prior art, many vacuum cleaners or floor cleaning apparatus are equipped with a power brush as part of a vacuum nozzle for removing dirt from the surface to be cleaned. The brush is driven by a motor. When the brush must stop under abnormal conditions such as blocked by something, the motor must first be shut down.

SUMMARY OF THE INVENTION

The present invention provides a power nozzle, the operation of which is controllable by a driving system. The inventive power nozzle comprises a nozzle housing or frame. A brush with bristles on its circumference is rotatably secured to the frame. A motor is secured to the frame and has a transmission shaft. A movable pulley assembly is connected to a position-control mechanism. A first drive belt runs around the pulley assembly and the power transmission shaft of the motor and a second drive belt runs around the pulley assembly and the brush. The position-control mechanism is constructed so that the movable pulley assembly can move between at least two positions. In the first position the axis of the movable pulley assembly is away from the transmission shaft of the motor with the first drive belt under tension by the pulley assembly and the motor. In the second position, the axis of the pulley assembly is close to the transmission shaft of the motor with the first drive belt being released from tension.

The invention is an improvement over the prior art in that the operation of the first belt can be changed by changing the position of the pulley assembly. Thus when the first drive belt is in tensioned state, the motor drives the brush to rotate via the pulley assembly. When the rotation of the brush is to be stopped, the first drive belt can be free from tensioned simply by changing the position of the movable pulley assembly without shutting down the motor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of the invention;

FIG. 2 is a side view of a first embodiment of the invention, showing the movable pulley assembly in a first position;

FIG. 3 is a side view of a first embodiment of the invention, showing the movable pulley assembly in a second position;

FIG. 4 is a side view of a second embodiment of the invention, showing the movable pulley assembly in a first position; and

FIG. 5 is a side view of a second embodiment of the invention, showing the movable pulley assembly in a second position.

DETAILED DESCRIPTION

Referring to FIGS. 1-5, a power nozzle of the present invention is shown. The power nozzle has a nozzle housing or frame 1. A rotatable cylindrical brush 2 having circumferential bristles is secured on the frame 1. A motor 7 is mounted to the frame 1 and has a transmission shaft 6. The power nozzle also has a movable pulley assembly 4, which is connected to a position-control mechanism 20. A first drive belt 5 loops around the pulley assembly 4 and the transmission shaft 6 of the motor. A second drive belt 3 is provided, which also around the pulley assembly 4 and the brush 2. The position-control mechanism is constructed to so that the movable pulley assembly 4 can move between at least two positions. In the first position the axis of the pulley assembly 4 is away from the axis of the transmission shaft 6 of the motor, which places the first belt 5 under tension (as shown in FIGS. 2 and 4). In the second position (as shown in FIGS. 3 and 5) the axis of the pulley assembly 4 is drawn close to the transmission shaft 6 of the motor with the first drive belt 5 being free from tension. Thus, the distance between the axis of the pulley assembly 4 and the transmission shaft 6 of the motor is less in the second position than when the movable pulley assembly is in the first position.

The invention is advantageous for a vacuum cleaner or floor cleaning apparatus in that the pulley assembly 4 is movable into its first position to place the first drive belt 5 under tension, which engages the transmission shaft 6 of motor 7 to drive the brush 2 to rotate in the agitation of dirt as needed for the vacuum cleaner. On the other hand, the pulley assembly 4 can be moved into its second position so that the first drive belt 5 can be free from tension and thus disengaged from the transmission shaft 6, whereupon the rotating cylinder 2 can be stopped immediately without shutting down the motor 7.

FIGS. 1-5 show the position-control mechanism according to two embodiments of the invention.

According to the first embodiment of the invention as shown in FIGS. 2-3, the position-control mechanism 20 incorporates a lever 9, which is pivotally attached to the frame 1 and includes an elongated slot 10. A crank rod 11 is privotably attached to the frame 1. The crank rod 11 carries a pin 12, which is disposed in the elongated slot 10 of the lever 9 on one end portion of the crank rod and the pulley assembly 4 at the other end portion.

In the present invention, the lever 9 and the crank rod 11 cooperate to enable the pulley assembly to selectably engage or disengage the drive belt 5 with the motor shaft 6. A pedal 8 is provided on the connecting lever 9 for toggling the pulley assembly between a first and a second position. When the pulley assembly 4 is placed in its first position, the brush 2 receives power from the transmission shaft 6 in rotational engagement with the pulley 4 by way of the drive belt 5 in tension, which power is in turn delivered to the brush 2 by drive belt 3.

When the rotation of brush 2 must be stopped for any reasons, the pedal 8 is actuated to rotate lever 9 in a clockwise, which in turn rotates crank rod 11 in the opposite direction until the pulley assembly 4 is moved to its second position.

When the pulley assembly 4 is in its first position, its axis 4 is on one side of a plane, which is defined by a line connecting the axis of the brush 2 and the axis of the pin 15 about which the crank rod 11 pivots relative to the frame 1. When the pulley assembly 4 is in its second position, the axis of the pulley assembly 4 is located on the opposite side of this plane. When the pulley assembly 4 moves between the first position and the second position, it pass through an intermediate and transitional position, in which position the axes of the pulley assembly 4 , the pivot pin 15 and the brush 2 are on the same plane. In this position, the distance between the axes of the pulley assembly 4 and the rotating cylinder 2 is the greatest than those when the pulley assembly 4 is in any positions between the first or second positions. When the pulley assembly 4 is in the transitional position, a tension applied on the pulley assembly 4 by the second drive belt 3 is sufficiently provided to urge the pulley assembly 4 to pass through the transitional position.

According to the second embodiment of the invention as shown in FIGS. 4-5, the position-control mechanism incorporates a crank rod 11 which is rotatably attached to the frame 1. The crank rod 11 is pivotally connected to the movable pulley assembly 4 and a pedal 8 is connected to the crank rod 11 via a common pivot. When the brush 2 is operated in the normal state, the pulley assembly 4 is in its first position automatically. When the operation of the brush 2 is to be stopped, the pedal 8 is actuated to pivot in a clockwise direction, which makes crank rod 11 to rotate clockwise. As a result, the pulley assembly 4 moves upwardly and the first drive belt 5 is released from tension.

Referring to all of the drawings, the pulley assembly 4 also incorporates a second pulley 13 and a first pulley 14 on the same shaft. The said second drive belt 3 loops around the second pulley 13 and the first drive belt 5 around the first pulley 14. As a speed reduction arrangement, the diameter of the second pulley 13 is less than that of the rotating cylinder 2 and the diameter of the first pulley 14 is larger than that of the transmission shaft 6 of the motor.

After reading this description it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation. As such, this detailed description of various alternative embodiments should not be construed to limit the scope or breadth of the present invention as set forth in the appended claims. 

1. A power nozzle for a vacuum cleaner comprising: a) a frame (1); b) a brush (2) rotataby secured in the frame; c) a motor (7) secured in the frame (1) and having a power transmission shaft (6); d) a pulley assembly (4) engageabe to rotationally couple with the motor shaft and the brush; and e) a position-control mechanism operative to selectively engage the pulley assembly (4) to couple with the transmission shaft (6) for the transmission of power from the motor (7) to the brush (2).
 2. The power nozzle according to claim 1, wherein the pulley assembly (4) is rotatably coupled to the transmission shaft (6) and the brush (2) by a drive belts (5) and (3) respectively.
 3. The power nozzle according to claim 2, wherein the position-control mechanism comprises (i) a lever (9) pivotably attached to the frame (1) and having an elongated slot (10), and (ii) a crank rod (11) pivotably attached to the frame (1) and having a pin (12) disposed in the elongated slot (10) and carrying the pulley assembly (4), such that the lever (9) and the crank rod (11) cooperate to enable the pulley assembly to selectably engage or disengage the drive belt (5) with the motor shaft (6).
 4. The power nozzle according to claim 2, which further comprises a foot pedal (8) affixed to the connecting lever (9) for the actuation thereof.
 5. The power nozzle according to claim 3, wherein the pulley assembly (4) carried by the crank rod (11) is movable between a first position and a second position such that in the first position, the axis of the pulley assembly (4) is on one side of a plane defined by a line connecting the axis of the brush (2) and the axis of the pivot pin (15) about which the crank rod (11) is rotatable relative to the frame (1), and in the second position, the axis of pulley assembly (4) is on the opposite side of the plane.
 6. The power nozzle according to claim 5 wherein when the pulley assembly (4) is moved between the first position and the second position, it passes through an intermediate position defined by a plane on which the axes of the pulley assembly (4), the pivot pin (15) and the rotating cylinder (2) are aligned with a longest distance between the axis of the pulley assembly (4) and the axis of the brush (2) than those when pulley assembly (4) is disposed in any other positions between the first position and the second position.
 7. The power nozzle according to claim 1 wherein the position-control mechanism includes (i) a crank rod (11) being attached to the frame (1) by a pivot and pivotally connected to the pulley assembly (4), and (ii) a pedal (8) connected to the crank rod (11) via a common pivot.
 8. The power nozzle according to claim 1, wherein at least one of the drive belts is constructed of an elastic material
 9. The power nozzle according to claim 2, said movable pulley assembly (4) comprises a first pulley (14) and a second pulley (13) both mounted on the transmission shaft, the first drive belt (5) running around the first pulley (14) and the second drive belt (3) running around the first pulley (13).
 10. The power nozzle according to claim 9 wherein the diameter of the first pulley (14) is larger than that of the transmission shaft (6) and the diameter of the second pulley (13) is less than that of the brush (2).
 11. A power nozzle for a vacuum cleaner comprising: a) a frame (1); b) a brush (2) rotataby secured in the frame; c) a motor (7) secured in the frame (1) and having a power transmission shaft (6); d) a movable pulley assembly (4) rotatably coupled to the transmission shaft (6) and the brush for the transmission of rotational power from the motor to the brush; and e) a positioning mechanism operative to effect engagement of the pulley assembly and the transmission shaft in a first position for the transmission of power from the motor shaft to the brush and for the disengagement of the pulley assembly with the transmission shaft in a second position. 